> ## Documentation Index
> Fetch the complete documentation index at: https://docs.solved.gg/llms.txt
> Use this file to discover all available pages before exploring further.

# Introduction

> rusty is a content-addressable Cargo + rustup replacement, rebuilt in Zig for Linux monorepos.

**rusty** is a Linux-only Rust project manager and toolchain manager rewritten in Zig. It combines content-addressable package storage, rustup-style toolchain control, and native resolve / fetch / build / test paths aimed at large monorepos — not a thin shell around `cargo`.

<Warning>
  **Linux only, permanently.** rusty relies on Linux filesystem semantics for the content store and build cache. macOS and Windows are not supported and will not be added.
</Warning>

## Why rusty exists

rusty started as an internal tool at **iResolved, LLC** on a client workspace with **3,676 crates** where Cargo could not keep a useful edit–build loop:

| Workload                      | Before (cargo) | With rusty       |
| ----------------------------- | -------------- | ---------------- |
| Cold build (no deps / cache)  | \~10 hours     | \~10 minutes     |
| Routine dev compiles          | \~6 hours      | \~45 seconds     |
| Peak speedup on routine tasks | —              | up to **\~400×** |

Those numbers come from that production monorepo shape — not a micro-benchmark. Your results depend on graph shape, cache hits, and whether the project is on the native path.

## What rusty does

* **Package manager** — init, lock, fetch, add, rm, update, clean; dual-mode for `rusty.json` / `rusty.lock` and Cargo-format trees during migration
* **Native build & test** — drives `rustc` directly for a declared project subset; hard-fails when a shape is unsupported (no silent cargo fallback for core verbs)
* **Toolchains** — install / use / list toolchains (rustup-like); default installs are `rustc` + `rust-std` only
* **Content store** — pnpm-style CAS under `$RUSTY_HOME` for crates and blobs
* **Layers & artifact cache** — per-crate differential cache and `RUSTC_WRAPPER` integration
* **Workspaces** — member listing, git-affected packages, reverse dependents, version-drift reports
* **Product auth** — optional Clerk-based identity for solved.gg / iResolved accounts (not crates.io login)

## What rusty is not (yet)

rusty is **early access**, not full Cargo parity. Prefer this framing:

> Dual-mode early access: native path for the rusty-format subset and growing cargo-format support; explicit cargo interop only for a small allowlist (`clippy`, `fmt`, `doc`, `bench`, `tree`) and opt-in install paths.

Do not expect every Cargo feature, registry edge case, or build-script shape to work natively on day one. Unsupported native builds fail closed with a clear error.

## Status at a glance

| Area                                                 | Native default?   | Notes                                                     |
| ---------------------------------------------------- | ----------------- | --------------------------------------------------------- |
| `lock` / `fetch` / `add` / `rm` / `update` / `clean` | Yes               | File I/O for both formats; no cargo process               |
| `build` / `run` / `check`                            | Yes (subset)      | Hard error if unsupported; optional `scripts.build`       |
| `test`                                               | Yes               | Never cargo by default; optional `scripts.test`           |
| `lint` / `format`                                    | Scripts           | Require `scripts.lint` / `scripts.format` in `rusty.json` |
| `clippy` / `fmt` / `doc` / `bench` / `tree`          | Interop           | Need cargo on PATH                                        |
| `install`                                            | Prebuilt → native | Cargo only with `RUSTY_INSTALL_ALLOW_CARGO=1`             |

## Next steps

<CardGroup cols={2}>
  <Card title="Quickstart" icon="rocket" href="/rusty/quickstart">
    Install a toolchain, scaffold a project, lock, fetch, and build.
  </Card>

  <Card title="Install" icon="download" href="/rusty/install">
    Get the rusty binary and set up `$RUSTY_HOME`.
  </Card>

  <Card title="Project formats" icon="file-code" href="/rusty/concepts/project-formats">
    rusty-format vs cargo-format and when to migrate.
  </Card>

  <Card title="CLI reference" icon="terminal" href="/rusty/reference/cli">
    Full command map from `rusty --help`.
  </Card>
</CardGroup>

## Product & license

* Site: [rusty.pm.solved.gg](https://rusty.pm.solved.gg)
* Suite hub: [pm.solved.gg](https://pm.solved.gg)
* Docs path: [`/rusty`](/rusty) on this site (not the suite root)
* License: **iResolved Source Available License v0.1** (source-available; not OSI open source). Authenticated solved.gg / iResolved accounts may use rusty under the applicable [EULA](/legal/eula) with payment portions of that license bypassed; other commercial licensing: contact iResolved LLC.
* Legal: [Privacy](/legal/privacy) · [Terms](/legal/terms) · [EULA](/legal/eula) · [CLA](/legal/cla)


## Related topics

- [Introduction](/pyppi/0.0.1-dev/index.md)